Patients must have inflammatory breast cancer or locally advanced breast cancer previously untreated with chemotherapy and/or radiation therapy. Inflammatory breast cancer is defined as histologically proven invasive adenocarcinoma of one breast with clinical inflammatory signs including onset of erythema and brawny induration or edema of the skin with an erysipeloid edge with or without an underlying tumor mass. Dermal lymphatic involvement by tumor cells is not a requirement for diagnosis. We will define locally advanced breast cancer as stage IIB, IIIA, or IIIC breast cancer according to the 2002 AJCC staging guidelines. Patients must have tissue accessible for serial biopsies.